Subtract 20/72 from 21/3
1st number: 7 0/3, 2nd number: 20/72
21/3 - 20/72 is 121/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 3 × 24 = 72,
21/3 = 21 × 24/3 × 24 = 504/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
20/72 = 20 × 1/72 × 1 = 20/72 - Subtract the two like fractions:
504/72 - 20/72 = 504 - 20/72 = 484/72 - After reducing the fraction, the answer is 121/18
- In mixed form: 613/18
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